The constitutional future of the island of Ireland is a contentious subject. In this paper we report on the outcomes of a highly participatory form of deliberation on Irish constitutional futures that—in our experimental cafés—recruited women across both sides of the Irish border and on a cross-community basis. We show that grassroots deliberation changed the terms of debate. It harnessed the potential of everyday peacebuilding and channelled it in politically relevant ways, focusing on shared policy problems and reframing the constitutional agenda. We emphasise the social and democratic value of the process in a still divided society and island. The purpose of this article is a proof of concept, offering a rationale for adopting the approach more widely. Our research is designed to explore the value of grassroots deliberation in framing and changing the constitutional agenda.